Improvement in safety tar-kilns



J. D. STANLEY.-

Safety Tar-kilns.

N0.57,645I Patented Dec. 8,1874.

l FIG-3;. gi, n Y \B 4. i B @n B WITN-Ess: INVBNTOH n UNITED y STATES PATENT @Erica JAMES nisrANLEv, 0E WILMINGTON, NoETi-r CAROLINA.

IMPROVEMENT IN SAFETV TAR-KILNS.

Specification formingr pari of Letters Patent No.157,645, dated December 8, i874; applicatiol` filed November 5, 1874. A

To all whom it may concern:

Beit known that I, J Ai/rEs D. STANLEY, of the city of Wilmington and State of North Carolina, have invented certain new and useful Improvements in Tar-Kilns, of which the following is a specification; and I do hereby declare that in the same is contained a full, clear, and exact description of my said invention, reference being had to the accompany- Sing drawing, and to the letters of reference marked thereon.

My invention relates to means, hereinafter fully described, for preventing explosions in tar-kilns, caused by the format-ion of a dangerous and explosive combin ation of gases therein during the operation aforesaid. My invention consists, first, in the v"adaptation of ventilating channels or stacks to the tar-kiln, constructed to carry olf the air contained therein, the current in the said stacks being accelerated and assisted by means of furnaces connected to, and in communication with, the channels or stacks aforesaid; and, secondly, in the applicationof a trap or seal to the tarpipe, in such manner as to prevent the admission of air from the exterior to the interior of the kiln by means of the said tar-pipe, during the tar-making operation.

In the description of my invention which follows due reference must be had to the accompanying drawing, forming a part ot' this specification, and in which- AFigure l is a longitudinal view of my iinproved tar-kiln, and Fig. 2 a cross-section of the same. Fig. 3 is a plan of the invention on a reduced scale.

Similar letters of reference indicate similar parts of the invention in both figures.

A is the kiln proper, preferably constructed of a rectangular form, and provided with a brick iioor, centrally elevated to form gutters at the sides of the kiln, to convey the tar to the tar-pipe hereinafter described. B B are ventilating channels or stacks, extending from below the floor of the kiln, at which place they connect with furnaces, hereafter described, to and through the roof of the same, and at their upper ends supplied with dampers a. The Ventilating-stacks B are perforated where exposed in the interior of the kiln, the said perforations forming the only means of conimunication between the kiln and the stacks and the exit-apertures for the air in the kiln. The kiln is supplied with the usual openings and doors for 'the manipulation of the wood during the stacking and burning processes. .O

is a trap, situated in the tar-delivery pipe in such manner as to prevent the admission of air to the kiln as the tar is being discharged. The furnaces hereinbefore alluded to, and which are designated in the drawing by D, extend from the stacks B to the exterior of the kiln, and are constructed in a manner applicable to the consumption of either coal or wood. The connections between the stacks and furnaces allow the en tire products of combustion of fuel in the furnaces to pass to and ascend in the stacks in a heated state.

To fully understand the object and utility of my invention, it must be understood that the gases arising from the consumption of wood are not inflammable unless combined with a certain proportion of oxygen, which is the supporter of combustion, and that although atmospheric air, which contains a certain proportion of oxygen, is necessarily admitted to the burning wood in the kiln, no danger or difficulty is experienced from such admission, as the air passes into the kiln only in such quantities as is necessary to combine with the other elements contained therein; but where the kiln is charged with air, as is the case upon the ignition of the wood at the commencement of the tar-making operation, and the air not Withdrawn from the kiln, the gases from the wood are urged into combination with the air until the constituent parts are in such relative proportions as to form a compound highly combustible in itself, and which, upon coming into contact with flame, explodes with great force. From this cause alone tar-kilns have always been considered as dangerous, and liable, after the ignition of the wood, to explode and destroy the building. In kilns, however, embodying my iin-v provements, the foregoing danger and difficulty are entirely obviated, as will be seen from the description of the operation of tarmaking which follows: The kiln having been stocked with wood, and the wood ignited, the dampers a are opened, and re made in the furnaces D. The products of combustion from the furnaces ascend through the stacks B, causing currents of air from the interior of the kiln to pass to the stacks by means of the perforations in the saine. By this means the air in the kiln is rapidly removed, and its place occupied by the gases from the Wood, which gases have, as hereinbefore stated, no inherent iniiammability, requiring, in combination With them, a certain proportion of air to render them explosive. Upon the removal of all the air from the kiln the tires in the furnaces may be extinguished, and the tar-making operation continued Without interruption until completed, the tar passing out through the trap C and pipe c connected thereto.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent ofthe United States, is

1. In a tar-kiln, the perforated stacks B, in combination with the furnaces D, substantially as set forth.

2. The combination of the tar-kiln A, trap C, and tar-pipe c, substantially as and for the purpose specified.

In testimony whereof I have hereunto subscribed my name this 21st day of October, A. D., 1874.

JAMES D. STANLEY.

Witnesses:

J No. T. MADDOX, WM. T. HOWARD. 

